An organic light emitting diode (OLED) is a new display technology, display quality of which can be compared with that of the thin film transistor liquid crystal display (TFT-LCD) devices and the price of which is much lower. The OLED has been increasingly becoming the focus of international research and development, due to its significant advantages in the panel display, such as high brightness, rich colors, low-voltage direct-current (DC) driving and simple preparation process. In less than 20 years OLED has entered the stage of industrialization.
In general, an OLED device is formed by depositing a transparent anode, a metal cathode and more than two organic layers sandwiched therebetween on a carrier which is a rigid glass substrate or a flexible polymer substrate. The organic layers typically include a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer and an electron injection layer and so on. The OLED device is very sensitive to oxygen and water vapor. If the oxygen and water vapor infiltrate into the OLED device, defects such as black spots, pinholes, electrode oxidations, organic material chemical reactions and the like will be caused, thereby seriously affecting the life of the OLED device.
Therefore, the OLED device needs to be packaged to inhibit the oxygen and water vapor from infiltration. A faceseal is one of the commonly used methods for packaging the OLED device. A faceseal process is generally divided into two steps: firstly, depositing inorganic passivation layer on the OLED device, then attaching a glass substrate having a waterproof and oxygenproof functional organic thin film under a nitrogen (N2) protection. FIG. 1 is a cross-sectional view showing a faceseal structure of a conventional OLED device. As shown in FIG. 1, the faceseal structure of the conventional OLED device is formed by a rigid surface glass substrate 1, an OLED device 2, a passivation layer 3, a to-be-cured resin layer 4 and an adhesive 5. Since both sides of the faceseal structure of the OLED device use rigid glasses as carrier plates, its flexibility, lighteness and thinness cannot be achieved.